GPAT 360

  LINCTUSES What is a Linctus? Linctuses are sweet, viscous liquid oral preparations containing medicinal substances which have demulscent, expectorant or sedative properties. These contain high proportions of syrup and glycerin which exert demulscent effect on the mucous membrane of throat. In order to obtain prolonged local action, linctuses should be administered slowly in undiluted form. Formulation of Linctus  1. Vehicle : Syrups are mostly used as vehicles in the linctuses. Tolu syrup is preferred in cough preparations due to its aromatic odor and flavour. Glycerol syrup and invert syrup are also used as vehicles. Linctus preparation for diabetic patients contain sorbitol syrup (vehicle). Medicament is first dissolved in little amount of water and then added into vehicle. Syrups are viscous and contain less amount of water, this limits (affects) the dissolution of medicament in syrup. 2. Additives: Colouring agents : Amaranth, Erythrosin, Tartrazine. Flavouring agents : ...

SYRUPS :  Monophasic Liquid Dosage Form Syrups are sweet and viscous or nearly saturated aqueous solutions of sugar or sugar substitute. Syrups containing therapeutic agent(s) are known as medicated syrups . Syrups containing flavouring agents but not medicinal substance / therapeutic agent are known as flavoured vehicles . Role/advantages of syrups : 1. Palatable : nauseous, bitter tasting, saline drugs can be administered with ease. 2. Pediatric patients : Medicated syrups are the most frequently administered dosage forms in pediatrics.  3. Little or no alcohol : Syrups are preferred for children due to less or no alcohol in syrups unlike elixirs. Commonly Used sweeteners in syrup formulations: 1. Sugars : Sucrose, Dextrose 2. Non-sugars : Sorbitol, Glycerin, propylene glycol. Why concentration of sucrose in sugar based syrup is important? Reasons are: the dilute solution of sucrose may cause microbial growth in formulation while the saturated sucrose solution may lea...

AROMATIC WATERS Aromatic waters are the saturated solutions of volatile oils or other aromatic substances.   Methods of preparation of aromatic waters: Distillation: Crude drug/material is placed in sufficient amount of purified water in flask. After heating water forms a steam which is condensed to obtain a condensate which contain aromatic principles. This method is expensive, tedious and time consuming. Examples: Orange flower water NF, Strong Rose water NF. Solution method: In this method, the volatile oil is shaken for 15 min with sufficient quantity (500 times) of water to make a solution. The resultant solution is kept aside for 12 hrs then filtered through wet filter paper.  Examples: Dill water, Peppermint water, Chloroform water, Camphor water, etc. Alternate solution method: The volatile oil is mixed with an inert adsorptive material ( Talc, Kieselghur, purified siliceous earth) then 1 ltr of purified water is added and agitated for 10 min. Resulting solution is...

MONOPHASIC LIQUID DOSAGE FORMS Mono-Single Monophasic – single phase dosage forms Examples: solutions, aromatic waters and tinctures A.   SOLUTIONS Monophasic system of two or more substances, e.g. sodium chloride solution, Pharmaceutical solutions are defined as the liquid preparations containing one or more chemical substances usually dissolved in water. Methods of preparation 1. Simple dissolution: Solute + suitable solvent → with/without heat → solution e.g. Morphine hydrochloride solution, Adrenaline hydrochloride solution. 2. Solution by chemical reaction: Reaction of two or more solutes → in suitable solvent. e.g. Aluminium acetate solution Al 2 (SO 4 ) 3 +3CaCO 3 +4CH 3 COOH → 2Al.(CH 3 COO) 2 .OH +3CaSO 4 +3CO 2 +H 2 O  3.  Solutions by extraction: Removal of active constituents from crude drugs with the help of solvent. e.g. liquid extracts and tinctures. Solutions for internal use: Taken orally: mixtures, elixirs, tinc...